Notes on No Subject - nosubject.io -

Migrating from WordPress to Hugo

Thu, 09 Jul 2026 00:00:00 +0900

I decided to migrate this site, which had been running on WordPress, to Hugo.

WordPress is convenient. You can write posts from the admin screen, and there are many themes and plugins. But after running it for a long time, the number of things to maintain keeps growing little by little: PHP, MySQL, plugins, themes, security updates, backups, and so on.

This blog is mostly a place where I leave notes about things I looked up. I do not need much dynamic behavior. For that kind of use, managing posts as Markdown files and publishing static HTML with Hugo feels like a better fit.

Switching the Raspberry Pi WordPress Site to Hugo

Thu, 09 Jul 2026 00:00:00 +0900

I already wrote about migrating the article data from WordPress to Hugo in Migrating from WordPress to Hugo.

This article covers the next step: switching the actual WordPress environment running on my Raspberry Pi to Hugo.

Even when I built the environment myself, I forget the details after enough time passes. Looking back at my older notes, this site was not running WordPress directly on the host with PHP and MySQL. It was running through Docker.

How I Improved the Loose USB Type-C Connection on My Google Pixel

Fri, 11 Jul 2025 18:51:09 +0900

Overview

I use Google Maps through Android Auto on my Pixel 7a as the car navigation system in my AQUA. Recently, the navigation would stop more often because of a loose USB Type-C connection.

I was having trouble finding a workaround, but then I came across information online saying that a Type-C connector can become unstable if it is inserted too deeply. This is what happened when I tried that idea.

Notes on Blocking Attacks Against Raspberry Pi SSH with Fail2Ban

Sun, 01 Sep 2024 23:16:45 +0900

Overview

I expose the SSH Server port so I can access my Raspberry Pi remotely, and when I looked at the logs, I saw that it was being attacked fairly often. Password login is disabled, so I could ignore it, but it felt unpleasant, so I configured Fail2Ban.

$ journalctl _COMM=sshd | grep "Invalid user"
Aug 11 09:23:53 pi4col sshd[1105]: Invalid user blank from 183.67.43.194 port 44130
Aug 11 09:44:30 pi4col sshd[1118]: Invalid user pi from 199.76.38.123 port 36840
Aug 11 09:44:30 pi4col sshd[1119]: Invalid user pi from 199.76.38.123 port 36844
Aug 11 09:45:33 pi4col sshd[1122]: Invalid user Admin from 138.75.192.20 port 52632
Aug 11 10:07:10 pi4col sshd[1197]: Invalid user blank from 61.83.254.100 port 38377
Aug 11 10:26:35 pi4col sshd[1268]: Invalid user nosubject from 152.136.41.3 port 55696
Aug 11 10:28:44 pi4col sshd[1270]: Invalid user admin from 121.7.26.195 port 50064
Aug 11 10:49:04 pi4col sshd[1282]: Invalid user babs from 81.70.27.122 port 45998
Aug 11 10:49:11 pi4col sshd[1284]: Invalid user zookeeper from 46.191.141.152 port 35283
...

What Is Fail2Ban?

Fail2Ban is a tool that checks access logs and bans addresses that repeatedly produce login errors, such as from brute-force attacks. This time, I use it to ban unauthorized SSH access.

Emacs Key Binding Settings for Sakura Editor

Wed, 14 Feb 2024 13:02:17 +0900

It is rough being in an environment where only Sakura Editor can be used.

Reposted from the following. (Because the environment could not even extract LZH files, I converted it to Zip.)

http://sakura.qp.land.to/?Customize%2F%C5%EA%B9%C6%2F6

SakuraEmacsKey Download

Type-specific settings for XML Download

Change the Windows 11 PIN (Windows Hello) Length from 6 Digits to 4 Digits

Wed, 09 Aug 2023 12:49:37 +0900

I use a PIN on Windows 11. By default, the minimum length was 6 digits, so I tried changing it to 4 digits.

Test Environment

OS: Windows 11 Pro 22H2 22621.2070
CPU: Core i7 13700
RAM: 64 GB

Configuration

Press Win + R (Run), enter gpedit.msc, and open the Local Group Policy Editor.

From the tree on the left, select Computer Configuration -> Administrative Templates -> System -> PIN Complexity. The Minimum PIN length item shown on the right is the setting for the number of PIN digits.
By default, it is Not configured (= 6 or more digits).

A Quick Way to Install WSL2 (Ubuntu) and Docker Desktop on Windows 11

Thu, 03 Aug 2023 12:13:54 +0900

This is a note from installing WSL and Docker Desktop in a Windows 11 Pro environment.

Overview

When using Docker containers on Windows, I use Docker Desktop.
For paid licensing and various other reasons, it seems people are moving away from Docker, but it is still easy and convenient when you want to verify something quickly.

On Windows 10, setting up WSL took a bit of work, but recent Windows 11 versions seem to install it quickly, so I wanted to try it.

[Python] What to Do When Sending Packets with Scapy as a General User Returns error: [Errno 1] Operation not permitted

Thu, 19 Jan 2023 10:56:58 +0900

Apparently, handling raw packets requires the Linux capability cap_net_raw.

The only apparent options are to run Python with sudo or grant the capability to /usr/bin/python3.

$ sudo setcap cap_net_raw=eip $(readlink -f $(which python3))

For a development environment, I think this is fine.

Reference: https://stackoverflow.com/questions/22421290/scapy-operation-not-permitted-when-sending-packets

How to Run SSHd with Systemd in a CentOS 7 Docker Container

Fri, 17 Jun 2022 20:05:58 +0900

I use Docker Desktop on Windows.

This time I needed to use Systemd on CentOS 7, so I looked into it.

Overview

If you run CentOS 7 in a container without doing anything special, running the systemctl command produces an error like this.

sh-4.2# systemctl start sshd
Failed to get D-Bus connection: Operation not permitted

https://hub.docker.com/_/centos/

リンク先を開く

hub.docker.com

To avoid this, you need to add options when starting the container. Docker Hub describes this, but even following those instructions did not work for me. The required settings seem to differ depending on the environment.

How to Change the Memory Limit in a Docker Desktop Environment

Wed, 15 Jun 2022 15:16:53 +0900

I run containers in a Docker Desktop environment, but they run with less memory than the physical memory available, so I tried increasing the memory allocation. This applies only to environments using the WSL 2 backend.

Overview

Docker Desktop is affected by WSL2's memory limit. On Windows 10, the default memory allocated to WSL2 appears to be 80% of the host memory. When I checked my own environments, they looked like this.

Can a mineo SIM Be Used in a WiMAX+ Wi-Fi Router, the Speed Wi-Fi NEXT W06?

Mon, 23 May 2022 22:46:23 +0900

This feels a little late, but I tried using a mineo SIM in a Speed Wi-Fi NEXT W06.

Background

Recently, I have liked mineo's 1GB data plan (880 yen/month) + Packet Unlimited Plus (385 yen/month).

If you are fine with a maximum speed of 1.5 Mbps, you can get an unlimited-data environment for about 1,300 yen per month. (If you are thinking about joining mineo, you can sign up at a discount through the referral link below.)

WENRUI (ROYAL KLUDGE RK61) Key Setting Shortcuts

Sat, 21 May 2022 18:16:02 +0900

Notes on switching keys on the WENRUI mechanical keyboard.

Overview

I use a mechanical keyboard sold as the "WENRUI Mechanical Keyboard", but inside it is a ROYAL KLUDGE RK61.

Customizing the Key Layout of the WENRUI (ROYAL KLUDGE RK61) Mechanical Keyboard

Tue, 08 Feb 2022 10:18:35 +0900

This is a note from when I tried customizing the key layout of the WENRUI mechanical keyboard (blue switches) that I bought on Amazon.

Overview

I bought a gaming keyboard on Amazon called the "WENRUI Mechanical Keyboard", and it was engraved ROYAL KLUDGE RK61.

[Raspberry Pi 4] USB Boot: Stop Using an SD Card and Boot from an SSD

Thu, 06 Jan 2022 17:12:07 +0900

This is a memo from migrating a Raspberry Pi web server that had been running from an SD card to an SSD with USB boot. I had written about something similar before; this time only the data-copying method is different. This procedure may be easier.
The steps are for Ubuntu, but I think almost the same method can be used with Raspberry Pi OS. This is amateur work, so follow it at your own risk if you use it as a reference.

[Raspberry Pi 4] Four-Channel Terrestrial Digital Recording Server on a Raspberry Pi: Docker + GPU Encoding Version

Sat, 18 Sep 2021 08:30:00 +0900

This is a memo for enabling hardware encoding in EPGStation running on a Raspberry Pi. It continues from the previous article, [Raspberry Pi 4] Four-Channel Terrestrial Digital Recording Server on Ubuntu with PX-Q1UD. Some parts still do not work perfectly, but the GPU appears to be usable, and it is mostly operational now.

This is amateur work, so follow it at your own risk if you use it as a reference.

[Raspberry Pi 4] Install Docker on the 64-bit Version of Raspberry Pi OS

Tue, 14 Sep 2021 13:51:47 +0900

This is a memo. It is the same procedure as installing on Ubuntu. The repository URL is about the only difference.

Test Environment

Raspberry Pi 4, 8GB memory
*On this site, I use a SanDisk SSD and a Buffalo SSD for storage. (Reference: [Raspberry Pi 4] Change the Pi 4 Storage from an SD Card to an SSD)

[Raspberry Pi] Configure Ubuntu Server Wi-Fi from CUI Commands

Mon, 13 Sep 2021 18:22:14 +0900

Overview

This is a note from installing Ubuntu Server on a Raspberry Pi, connecting a display and keyboard, and configuring Wi-Fi. With the Desktop edition, you can configure it from the GUI, so you probably do not need to do it from commands.

If you want to install and configure it without connecting a display or keyboard, see "[Raspberry Pi 4] Headless Install of Ubuntu Server 21.04 (No Monitor or Keyboard) Beginner-Friendly".

[Raspberry Pi 4] Increase the Memory Allocated to the GPU

Thu, 09 Sep 2021 17:50:49 +0900

Overview

The Raspberry Pi GPU memory is shared with system memory.

I checked how to change the amount of memory allocated to the GPU.

Test Environment

Raspberry Pi 4 with 8GB RAM, running Ubuntu.

$ cat /proc/device-tree/model Raspberry Pi 4 Model B Rev 1.4

$ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 21.04 Release: 21.04 Codename: hirsute

Configuration

Check the current GPU memory size. By default, the allocation to the GPU seems to be 76MB.
There is plenty of system memory available, so I will increase the GPU allocation.

[Raspberry Pi 4] Four-Channel Simultaneous Terrestrial Digital TV Recording Server on Ubuntu with PX-Q1UD

Sat, 19 Jun 2021 00:21:28 +0900

These are notes. I tried something called a recording server. Since I already had a Docker environment, it was easy to create. I also tried hardware encoding, but it was not stable, so these notes only cover building the normal setup. This is amateur work, so if you use it as a reference, do so at your own risk.

Update: In a separate article, I wrote about operating it with H/W encoding.
[Raspberry Pi 4] [Redo] Four-channel simultaneous terrestrial digital TV recording server on Raspberry Pi

Trying an ahamo (docomo) SIM with Speed Wi-Fi HOME L02 / NEXT W06

Mon, 12 Apr 2021 22:17:58 +0900

I canceled WiMAX 2+ because using an ahamo SIM seemed cheaper, so I tried whether an ahamo SIM could be used with Speed Wi-Fi HOME L02 / NEXT W06.

Background

When there is less than a year left before the contract renewal, WiMAX 2+ recommends another three-year contract renewal under the premise of changing the Wi-Fi router model and making the device fee free.
However, with mobile carriers competing to lower data communication prices, I do not feel eager to renew for three years just because the monthly fee becomes a little cheaper and I can get a new device.